Improved radiopharmaceuticals for imaging cerebral acetylcholinesterase (AChE) are needed for the diagnosis of Alzheimer's disease (AD). Thus, (11)C-labeled (-)-galanthamine and its enantiomers were synthesized as novel agents for imaging the localization and activity of AChE by positron emission tomography (PET). C-11 was incorporated into (-)- and (+)-[(11)C]galanthamine by N-methylation of norgalanthamines with [(11)C]methyl triflate.
View Article and Find Full Text PDFMalaria remains as one of the most devastating infectious disease, and continues to exact an enormous toll in medical cost and days of labor lost especially in the tropics. Effective malaria control and eventual eradication remain a huge challenge, with efficacious antimalarials as important intervention/management tool. Clearly new alternative drugs that are more affordable and with fewer side effects are desirable.
View Article and Find Full Text PDF3α-Methoxyserrat-14-en-21β-ol (PJ-1) and 3β-methoxyserrat-14-en-21β-ol (PJ-2) were conjugated with well-known phenolic compounds, narigenin, hesperetin, genistein, and daidzein (1-8). Other conjugates of PJ-2-3,5-dihydroxy-4-methoxybenzoic acid (9), PJ-2-pyrogallol (10), and derivatives of PJ-1, PJ-2-3,3-dimethyl-succinates (11, 12), PJ-1, PJ-2-succinates (13, 14), PJ-2-glycine (15), PJ-2-piperidine acetic acid (16), and PJ-1 epoxy-3,3-dimethyl-succinate (17) were tested for their inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA). The inhibitory effects of 11 (IC(50) = 251), 12 (IC(50) = 248), and 17 (IC(50) = 230 mol ratio/32 pmol/TPA), were 2-fold stronger than those of the other compounds such as oleanolic acid (IC(50) = 449).
View Article and Find Full Text PDF3alpha-methoxyserrat-14-en-21beta-ol (1) and 3beta-methoxyserrat-14-en-21beta-ol (2) and their conjugates with curcumin, kojic acid, quercetin, and baicalein (3-18), as well as new analogs (19-24) derived from 1 and 2, were tested for their inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA). The inhibitory effects of 16 (IC50=330 mol ratio/32 pmol/TPA), 9 (IC50=335), 10 (IC50=338), and 15 (IC50=350) were stronger than those of the other compounds and the positive control, oleanolic acid (IC50=449). Compounds 15 and 16, which are conjugates of one molecule each of 1 or 2 and quercetin, inhibited mouse skin tumor promotion in an in vivo two-stage carcinogenesis model.
View Article and Find Full Text PDFSixteen novel compounds; 3alpha-methoxyserrat-14-en-21beta-ol (1) and 3beta-methoxyserrat-14-en-21beta-ol (2) and their curcumin, kojic acid, quercetin, and baicalein conjugates (3)-(18) were designed, synthesized, and evaluated for in vitro anti-HIV-1 reverse transcriptase (RT) activity in infected C8166-CCR5 cells, a human CD4(+) T-lymphocyte cell line. Among them, kojic acid derivatives, 9-12 showed significant biological activity. In particular, the compound 13, the conjugate of two molecules of 3alpha-methoxyserrat-14-en-21beta-ol (1) and one molecule of kojic acid, exerted significant anti-HIV activity with an EC50 value of 0.
View Article and Find Full Text PDFPurpose: Transforming growth factor beta receptor (TGFbeta-R) is reported to correlate with the malignant potential of scirrhous gastric carcinoma. The aim of the current study is to clarify the possibility of molecular target therapy with a TGFbeta-R inhibitor, A-77, for the treatment of peritoneal dissemination of scirrhous gastric cancer.
Experimental Design: Three scirrhous gastric cancer cell lines and two fibroblasts were used.
(+/-)-Galanthamine (1) was synthesized in excellent yield by applying PIFA-mediated oxidative phenol coupling of N-(4-hydroxy)phenethyl-N-(3',4',5'-trialkoxy)benzyl formamide (15b) as a key step. Because of the symmetrical characteristics of the pyrogallol moiety in the substrate (15b), the phenol coupling resulted in a sole coupling product except for volatile components from the oxidizing agent. On the basis of the successful results of the above strategy, (-)-galanthamine (1) was synthesized by employing a novel remote asymmetric induction, where conformation of the seven-membered ring in the product of the phenol coupling was restricted by forming a fused-chiral imidazolidinone ring with D-phenylalanine on the benzylic C-N bond of the tri-O-alkylated gallyl amino moiety.
View Article and Find Full Text PDFDerivatives of 2'-deoxyuridine that contain fluoroalkyl groups at the C5 position and derivatives of thymidine that contain fluoroalkyl groups at the N3 position were synthesized and examined in three in vitro assays designed to evaluate their potential as radiopharmaceuticals for imaging cellular proliferation. Three of the former nucleosides and five of the latter were synthesized. The three assays were as follows: (a) phosphoryl transfer assay, which showed that all three of the former nucleosides and four of the latter ones were phosphorylated by recombinant human thymidine kinase 1 (TK1) and that N(3)-(2-fluoroethyl)-thymidine (NFT202) was the most potent substrate of the eight nucleosides studied; (b) transport assay, which indicated that all eight nucleosides had good affinity for an 6-[(4-nitrobenzyl)thio]-9-beta-d-ribofuranosylpurine-sensitive mouse erythrocyte nucleoside transporter, with inhibition constants in the range of 0.
View Article and Find Full Text PDFTransforming growth factor (TGF)-beta signaling facilitates tumor growth and metastasis in advanced cancer. Use of inhibitors of TGF-beta signaling may thus be a novel strategy for the treatment of patients with such cancer. In this study, we synthesized and characterized a small molecule inhibitor, A-83-01, which is structurally similar to previously reported ALK-5 inhibitors developed by Sawyer et al.
View Article and Find Full Text PDFAfter radiation therapy of lung cancer, a dense fibrotic shadow develops in the irradiated lung. Owing to this fibrosis, early detection of local recurrence after treatment is sometimes difficult even when using computed tomography (CT) and magnetic resonance imaging. We investigated the diagnostic accuracy of technetium-99m hexakis 2-methoxyisobutylisonitrile ((99m)Tc-MIBI) scintigraphy for the detection of recurrent lung cancer following definitive radiation therapy.
View Article and Find Full Text PDFBackground: Vitamin D-binding protein (DBP) has been recognized as a multifunctional plasma protein that can modulate certain immune and inflammatory responses. There may be differences between the DBP concentrations in pleural fluids from various diseases involving a variety of possible responses in the pleural cavity.
Methods: An anti-DBP polyclonal antibody was prepared using commercially available DBP to establish a quantitative measuring system for DBP.